From bb8eb7063c998003a8b3d3ff30bb9c4075d80b3f Mon Sep 17 00:00:00 2001
From: Sai Ganesh Muthuraman <saiganeshm@google.com>
Date: Thu, 21 May 2026 23:39:50 -0700
Subject: [PATCH] Enable scroll and zoom out in Trace Viewer V2 when loading
 deep-linked traces.

PiperOrigin-RevId: 919479016
---
 .../trace_helper/trace_pb_event_parser.cc     |  9 ++++++++
 .../xprof/protobuf/trace_data_response.proto  |  3 +++
 ...ce_data_to_compressed_delta_series_proto.h |  7 ++++++
 ...a_to_compressed_delta_series_proto_test.cc | 23 +++++++++++++++++++
 4 files changed, 42 insertions(+)

diff --git a/frontend/app/components/trace_viewer_v2/trace_helper/trace_pb_event_parser.cc b/frontend/app/components/trace_viewer_v2/trace_helper/trace_pb_event_parser.cc
index a8402becb..b4118ab81 100644
--- a/frontend/app/components/trace_viewer_v2/trace_helper/trace_pb_event_parser.cc
+++ b/frontend/app/components/trace_viewer_v2/trace_helper/trace_pb_event_parser.cc
@@ -57,6 +57,15 @@ ParsedTraceEvents ParseCompressedTraceEvents(
   ProcessAsyncEvents(response, result);
   ProcessCounterEvents(response, result);
 
+  if (response.has_full_timespan_start_ps() &&
+      response.has_full_timespan_end_ps()) {
+    const Milliseconds start_ms = response.full_timespan_start_ps() / 1e9;
+    const Milliseconds end_ms = response.full_timespan_end_ps() / 1e9;
+    if (start_ms <= end_ms) {
+      result.full_timespan = std::make_pair(start_ms, end_ms);
+    }
+  }
+
   if (!visible_range_from_url.isNull() &&
       !visible_range_from_url.isUndefined() &&
       visible_range_from_url["length"].as<int>() == 2) {
diff --git a/plugin/xprof/protobuf/trace_data_response.proto b/plugin/xprof/protobuf/trace_data_response.proto
index 2b84b351f..343c6caea 100644
--- a/plugin/xprof/protobuf/trace_data_response.proto
+++ b/plugin/xprof/protobuf/trace_data_response.proto
@@ -84,4 +84,7 @@ message TraceDataResponse {
   repeated string interned_strings = 5;
   // Details for the trace (e.g., flags for the frontend).
   repeated DetailItem details = 6;
+  // The full timespan of the trace (start time and end time in picoseconds).
+  optional uint64 full_timespan_start_ps = 7;
+  optional uint64 full_timespan_end_ps = 8;
 }
diff --git a/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto.h b/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto.h
index a88a13b01..6fd7144e6 100644
--- a/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto.h
+++ b/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto.h
@@ -134,6 +134,13 @@ absl::Status DeltaSeriesProtoConverter::GenerateResponse(
     d->set_value(detail.second);
   }
 
+  if (trace_->has_min_timestamp_ps()) {
+    response->set_full_timespan_start_ps(trace_->min_timestamp_ps());
+  }
+  if (trace_->has_max_timestamp_ps()) {
+    response->set_full_timespan_end_ps(trace_->max_timestamp_ps());
+  }
+
   using TidOrName = std::variant<uint64_t, absl::string_view>;
 
   container.ForAllTracks([this, response](uint32_t pid, TidOrName tid_or_name,
diff --git a/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto_test.cc b/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto_test.cc
index 394354e08..269db4bdd 100644
--- a/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto_test.cc
+++ b/xprof/convert/trace_viewer/delta_series/trace_data_to_compressed_delta_series_proto_test.cc
@@ -15,6 +15,7 @@ namespace tensorflow {
 namespace profiler {
 namespace {
 
+using ::testing::Eq;
 using ::testing::EqualsProto;
 using ::testing::proto::Partially;
 
@@ -416,6 +417,28 @@ TEST(DeltaSeriesProtoConverterTest, PopulatesDetails) {
               )pb")));
 }
 
+TEST(DeltaSeriesProtoConverterTest, PopulatesFullTimespan) {
+  Trace trace;
+  trace.set_min_timestamp_ps(12345000);
+  trace.set_max_timestamp_ps(67890000);
+  TestTraceEventsContainer container(trace);
+
+  ASSERT_OK_AND_ASSIGN(std::string compressed_result,
+                       ConvertTraceDataToCompressedDeltaSeriesProto(
+                           DeltaSeriesProtoConversionOptions{}, container));
+
+  ASSERT_OK_AND_ASSIGN(std::string decompressed,
+                       ZstdCompression::Decompress(compressed_result));
+
+  xprof::TraceDataResponse response;
+  ASSERT_TRUE(response.ParseFromString(decompressed));
+
+  EXPECT_TRUE(response.has_full_timespan_start_ps());
+  EXPECT_THAT(response.full_timespan_start_ps(), Eq(12345000));
+  EXPECT_TRUE(response.has_full_timespan_end_ps());
+  EXPECT_THAT(response.full_timespan_end_ps(), Eq(67890000));
+}
+
 }  // namespace
 }  // namespace profiler
 }  // namespace tensorflow